Deep learning is a rapidly growing discipline that models high-level patterns in data as complex multilayered networks. Because it is the most general way to model a problem, deep learning has the potential to solve the most challenging questions in machine learning and artificial intelligence. Companies like Microsoft and Google use deep learning to solve difficult problems in areas such as speech recognition, image recognition, 3-D object recognition, and natural language processing.
However, deep learning requires considerable computing power to construct a useful model. Until recently, the cost and availability of computing limited its practical application. Moreover, researchers lacked the theory and experience to apply deep learning to practical problems. Given available time and resources, other methods often performed better.